A galvanometer of 90 ohms internal resistance has a full-scale current of 350. microA. Describe how to use this meter to make : (a) a 150 V voltmeter, and (b) a 10.0A ammeter

So (a) Resistors must be connected in series with the galvanometer, R=4.29 x 10^5 ohms.

(b) A shunt resistor must be used in parallel with the galvanometer. :rofl:

Find the voltage required to give the galvanometer coil full deflection and then figure out what resistor carrying 10 amps of current will provide that voltage drop. That resistor placed in parallel with the galvanometer will be a 10 amp ammeter.